1. Field of the Invention
The present invention relates to a heat exchange for a vehicle. More particularly, the present invention relates to a heat exchanger for a vehicle that efficiently cools LPG fuel by exchanging heat between LPG fuel returned to a bombe from an engine of an LPI vehicle and refrigerant that is circulated in an air-conditioning system.
2. Description of Related Art
In general, a liquefied petroleum injection (LPI, an LPG liquefied fuel injection device) engine is an engine (Mono-fuel mode) having a fuel pump installed in a bombe and injects liquefied fuel for each cylinder by using an injector by liquefying LPG fuel at high pressure (5 to 15 bar) by the fuel pump, unlike a mechanical LPG fuel mode that depends on the pressure of a bombe.
Since the LPI engine injects liquefied fuel, components such as a vaporizer, a mixer, and the like which are constituent members of a mixer type LPG engine are not required, and the LPI engine includes a high-pressure injector, the fuel pump installed in the bombe, a fuel supply line, an electronic control unit (ECU) exclusively for LPI, and a regulator unit regulating fuel pressure.
The electronic control unit of the LPI engine determines a state of the engine by receiving input signals of various sensors and controls a fuel pump, an injector, and an ignition coil for improvement of an optimal air-fuel ratio and engine performance.
In addition, the liquefied fuel is supplied to the engine by controlling the fuel pump according to a fuel amount required in the engine, and an LPI injector sequentially injects fuel for each cylinder.
However, in a vehicle to which an LPI system in the related art is applied, as high-temperature return fuel is returned to the bombe from the engine, a phenomenon occurs, in which internal pressure of the bombe rises due to an increase in temperature of the LPG fuel. In particular, when the internal pressure of the bombe is higher than charge pressure of a gas station, the LPG fuel cannot be charged in the bombe.
As a result, since an additional fuel cooling device needs to be installed in order to decrease the temperature of the fuel returned from the engine, manufacturing and installation costs increase and there is a limit in securing installation space in a narrow engine room.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.